def __init__(self, filePath, maxAvatarSizeValue):
self.storageSystem = SQLiteAvatarStorageSystem(filePath)
self.maxAvatarSizeValue = maxAvatarSizeValue
self.avatarFetcher = ConnectionCachingFetcher(TIMEOUT_TIME)
class PersistentAvatarCache(object):
def __init__(self, filePath, maxAvatarSizeValue):
self.storageSystem = SQLiteAvatarStorageSystem(filePath)
self.maxAvatarSizeValue = maxAvatarSizeValue
self.avatarFetcher = ConnectionCachingFetcher(TIMEOUT_TIME)
def open(self):
self.storageSystem.open()
def close(self):
self.storageSystem.close()
def __convertHTTPObjectToAvatar(self, url, httpObj):
data = filterImageDataToVersionWithinSizeRestriction(httpObj.data, self.maxAvatarSizeValue)
lastModified = httpObj.lastModified
return Avatar(url, data, lastModified)
def __downloadAvatar(self, avatarURL):
httpObj = self.avatarFetcher.downloadHTTPObject(avatarURL, MAX_DOWNLOAD_SIZE)
return self.__convertHTTPObjectToAvatar(avatarURL, httpObj)
def __updateRecordedAvatarURL(self, user, oldURL, newURL):
self.storageSystem.updateUserAvatarURL(user, newURL)
self.storageSystem.cleanCachedAvatarIfUnused(oldURL)
def __getAvatarURL(self, user, avatarURL):
recordedAvatarURL = self.storageSystem.getUserAvatarURL(user)
if avatarURL == None:
return recordedAvatarURL
if recordedAvatarURL == None:
self.storageSystem.storeUserAvatarURL(user, avatarURL)
elif recordedAvatarURL != avatarURL:
self.__updateRecordedAvatarURL(user, recordedAvatarURL, avatarURL)
return avatarURL
def __downloadAvatarIfUnmodified(self, avatarURL, lastModified):
httpObj = self.avatarFetcher.downloadHTTPObjectIfModified(avatarURL, lastModified, MAX_DOWNLOAD_SIZE)
if httpObj == None:
return None
return self.__convertHTTPObjectToAvatar(avatarURL, httpObj)
def __refreshAvatar(self, cachedAvatar):
try:
newAvatar = self.__downloadAvatarIfUnmodified(cachedAvatar.url, cachedAvatar.lastModified)
except:
return cachedAvatar
if newAvatar == None:
return cachedAvatar
self.storageSystem.updateCachedAvatar(newAvatar)
return newAvatar
def getAvatar(self, user, avatarURL):
try:
avatarURL = self.__getAvatarURL(user, avatarURL)
if avatarURL == None:
return None
cachedAvatar = self.storageSystem.getAvatar(avatarURL)
if cachedAvatar == None:
avatar = self.__downloadAvatar(avatarURL)
self.storageSystem.storeCachedAvatar(avatar)
else:
avatar = self.__refreshAvatar(cachedAvatar)
self.storageSystem.commitUncommittedChanges()
return avatar.data
except Exception, e:
self.storageSystem.rollbackUncommittedChanges()
raise e
